CN101234481B - Polishing pad with grooves to retain slurry on the pad texture and its preparation method - Google Patents

Abstract

A rotational chemical mechanical polishing pad designed for use with a polishing medium. The polishing pad includes a polishing layer having a polishing surface containing a plurality of grooves. At least a portion of each of the plurality of grooves has a shape and orientation determined as a function of the trajectory of the polishing medium during use of the pad.

Description

Have and be used for polishing pad that slurry is retained in the constructional groove of polishing pad and preparation method thereof

Technical field

The present invention relates generally to chemically mechanical polishing (CMP) field.Specifically, the present invention relates to have the CMP pad of the groove that reduces slurry consumption.

Background technology

In integrated circuit on semiconductor wafer and the manufacturing of other electronic devices, deposit multilayer conductive material, semi-conducting material and dielectric material on wafer are perhaps removed the etching from the wafer of multilayer conductive material, semi-conducting material and dielectric material.The thin layer of these materials can be by many kinds of techniques of deposition.Conventional deposition technique comprised chemical vapour deposition (CVD) (PECVD) and the electrochemistry plating that physical vapour deposition (PVD) (PVD is also referred to as sputter), chemical vapor deposition (CVD), plasma strengthen during modern wafer was handled.General etching technique comprises the isotropic etching of wet method and dry method and anisotropic etching etc.

Along with material layer is deposited and etching in order, it is uneven that the surface of wafer becomes.Because semiconductor machining (for example photoetching) subsequently requires this wafer to have flat surfaces, so need periodically carry out complanation to wafer.Complanation can be used for removing undesirable surface topography and blemish, for example rough surface, agglomerated material, crystal lattice damage, cut and contaminated layer or material.

Chemical-mechanical planarization, or claim that chemically mechanical polishing (CMP) is a kind of ordinary skill that semiconductor wafer and other workpiece are carried out complanation of being used for.In the conventional CMP that uses twin shaft rotation polishing machine, chip support or rubbing head are installed on bracket component.Described rubbing head holding chip, make wafer orientation with polishing machine in the contacted position of polishing layer of polishing pad.The diameter of described polishing pad is greater than the twice of the diameter of flattened wafer.In polishing process, polishing pad and wafer make wafer contact with polishing layer around they coaxial center rotations separately simultaneously.The rotation of described wafer is with respect to one section distance greater than wafer radius of the rotation of polishing pad skew, makes " the wafer track " that scans out an annular on the polishing layer that is rotated in polishing pad of polishing pad.When wafer only was rotated motion, the width of described wafer track equaled the diameter of wafer.But in some twin shaft polishing machines, described wafer vibrates in the plane perpendicular to its rotation.In the case, the width of wafer track is wideer than wafer diameter, the wide scale that goes out show the displacement that vibration causes.Described bracket component provides controlled pressure between described wafer and polishing pad.In polishing process, slurries or other polishing medium flow on the polishing pad, flow in the gap between wafer and the polishing layer.By polishing layer and polishing medium chemical action and the mechanism to wafer surface, wafer surface is polished and flatten.

People in the CMP process between polishing layer, polishing medium and the wafer surface Study of Interaction more and more, to make great efforts to make the design optimization of polishing pad.In these years, most polishing pad exploitation is experimental.The design of many burnishing surfaces or polishing layer is primarily focused on to these layers provide various void pattern and groove arrangement, and claims that these designs can improve the uniformity that slurries utilize ability and polishing.In these years, people have used many different groove patterns and arrangement, and many different void pattern and arrangement.The groove pattern of prior art comprises radiation shape, circular concentric, Descartes's grill-shaped and spirality etc.The groove configuration of prior art comprise fluted width and the configuration of degree of depth homogeneous, and the configuration that differs from one another of the width of groove and the degree of depth.

Really, how most of groove pattern responds the deduction of various notch feature (for example groove curvature and groove cross section) based on slurries are flowed.These features often have material impact to the migration of the slurries that distribute under the centripetal force effect that produces at the rotation polishing machine.When the orientation of groove from more for hoop become more for radially the time, the migration increase that the slurries of distribution are outside.For example, groove radially can make the at utmost radially outflow of slurries of distribution by being similar to the effect of passage, causes liquid directly all to flow out polishing pad.This outflow causes the contact point between polishing pad and the wafer surface overheated, causes the problem of polishing performance variation and polishing pad abrasion increase and so on, thereby polishing process is caused negative effect.

Because polishing pad has many kinds of groove patterns, the effect of these groove patterns differs from one another, and in different glossings, its effect also is different.The polishing pad designer is constantly seeking to make polishing pad the design more effective and more useful groove pattern of polishing pad with respect to prior art.

Summary of the invention

One aspect of the present invention relates to a kind of polishing pad that is used in combination with polishing medium, described polishing medium has desirable flow path, described desirable flow path is in use rotated by polishing pad and provides, wherein said polishing pad comprises: design is used in the presence of polishing medium at least a polishing layer that polishes in magnetic base material, optical element and the semiconductor substrate, described polishing layer comprises circular burnishing surface, and this burnishing surface has the annular polishing track in polishing process; Be formed at least one groove in the described polishing layer, it has the quadrature component that is positioned at described polishing locus, and described quadrature component has certain-length, is shaped along whole length, along quadrature component and perfect fluid flow path quadrature.

Another aspect of the present invention relates to a kind of polishing pad, and it comprises: design is used in the presence of polishing medium at least a polishing layer that polishes in magnetic base material, optical element and the semiconductor substrate; Be formed at least one groove in the described polishing layer, it has the quadrature component that is positioned at polishing locus, and described quadrature component has certain-length, is shaped according to following formula

$r^{*}=r_o{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">e</figure-callout>}}^{\frac{1}{2}{\left(3\mathrm{\&theta;}\right)}^{2/3}}$

R in the formula _oBe and the initial radial position apart, coaxial center of polishing pad, θ is the flow path angle.

Another aspect of the present invention relates to a kind of preparation method who is used for the rotating polishing pad that uses with polishing medium, and this method comprises: the flow path of determining polishing medium; Shape and the orientation determining in rotating polishing pad, to form as the groove of the function of polishing medium flow path; In described rotating polishing pad, form the groove that has described groove shapes and groove orientation in a large number.

Description of drawings

Fig. 1 is the plane of polishing pad constructed in accordance;

Fig. 2 is the amplification sectional view of the polishing pad of Fig. 1 along Fig. 1 cathetus 2-2 intercepting;

Fig. 3 is the schematic top plan view of the polishing pad of Fig. 1, has shown the shape of a groove on the polishing pad with respect to the perfect fluid flow path among the figure;

Fig. 4 is the floor map of another kind of polishing pad constructed in accordance, has shown the shape of a groove on the polishing pad among the figure;

Fig. 5 is the plane of the polishing pad of Fig. 4, has shown the complete structure of described polishing pad among the figure;

Fig. 6 is the floor map of another kind of polishing pad constructed in accordance, has shown the shape of a groove on the polishing pad among the figure;

Fig. 7 is the plane of the polishing pad of Fig. 6, has shown the complete structure of polishing pad among the figure;

Fig. 8 is the schematic diagram according to polishing system of the present invention.

Detailed Description Of The Invention

Refer now to accompanying drawing, Fig. 1 and Fig. 3 have shown an embodiment of polishing pad constructed in accordance 100.As discussed below, polishing pad 100 designs in one way, and this design has stoped polishing medium (showing among the figure, for example slurries) because of the centripetal force effect of the polishing pad 100 that in use the rotated trend to external migration.Usually, polishing pad 100 comprises the burnishing surface 104 that contains a plurality of grooves 108, each groove 108 has groove shapes 112 (Fig. 3), this groove shapes 112 is at least in part as the function of fluid flow path 116 (Fig. 3) and determine, if there is no groove 108, in the process of using, when polishing pad rotated, described fluid flow path 116 can be determined the average path of following when polishing medium moves.More particularly, select feasible corresponding each groove 108 and fluid flow path 116 quadratures to all or part of groove shapes 112 and with respect to the orientation of polishing pad 100 direction of rotation.Therefore, the trend that flows through burnishing surface 104 with the groove 108 of fluid flow path 116 quadratures or 108 pairs of polishing mediums of wherein a part of groove and leave polishing pad 100 has produced significant obstruction, thereby has prolonged the time of staying of polishing medium on polishing pad.It is less that the time of staying that prolongs causes polishing medium to consume, so running cost is lower.Describe the various exemplary geometric structures of groove 108 below in detail.

Referring to Fig. 1 and Fig. 2, polishing pad 100 can comprise the polishing layer 120 (Fig. 2) that forms burnishing surface 104.In an example, polishing layer 120 can be subjected to back sheet 124 supportings, and described back sheet 124 can form with polishing layer 120 globalities ground, perhaps can form independently of one another with polishing layer 120.Fig. 1 again, polishing pad 100 has the shape of disk usually, so burnishing surface 104 has center of circle O and circular outer periphery 128.The latter can be positioned at the position at a distance of certain radial distance with O, is expressed as R among the figure _PadPolishing layer 120 can be made by any material that is fit to be used for to polished goods polish, described goods such as semiconductor wafer, magnetic medium goods (for example disk of computer hard disc driver) or eyeglass (for example refractive lens, reflection lens), plane reflector or transparent flat article etc.The examples of material that is used for polishing layer 120 includes but not limited to, various polymer plastics, for example polyurethane, polybutadiene, Merlon and polymethacrylates etc.

Can be in any suitable manner in polishing layer 120, form each in a plurality of grooves 108, for example by mill, molding etc.In one embodiment, the groove 108 of formation is disconnected from each other, repeats to be provided with around center of circle O with constant pitch.In addition, each groove in formed described a plurality of grooves 108 can have required groove cross section shape 132 (Fig. 2), to adapt to one group of specific design standard.In one embodiment, each groove in described a plurality of grooves 108 can have the shape of cross section of rectangle, for example shape shown in the figure further groove shape of cross section 132a.In another embodiment, each groove 108 can have the groove cross section 132 that changes along its length.In another embodiment, the shape of cross section 132 of different grooves 108 can change.Those of ordinary skills can understand, and the designer can provide the groove cross section shape 132 and the various application thereof of wide range for polishing pad (for example polishing pad 100).

Fig. 3 again, described fluid flow path 116 be when burnishing surface 104 be dredge (for example hydrophobic) of fluid and do not contain any groove 108 or other when hindering the structure of fluid motion, the desirable flow path that fluid (for example water) will be taked under the influence of polishing pad 100 rotations.Following mathematics is deduced and is based on this desirable flow path.Yet, people recognize that the true flow path of polishing medium on actual pad interface may be different from the variation of desirable flow path owing to the influence of various factors, and described factor comprises polishing medium viscosity and the surface tension of for example not considering in idealized flow path.Therefore, fluid flow path 116 has also shown when the physical force that polishing pad 100 applied when specific polishing medium and polishing pad rotation respond, the true flow path of this polishing medium.But in this manual,, only list in detail below for the mathematics of desirable accessible flow path and deduce in order to simplify explanation to notion.This means that not necessarily this specification only comprises the groove shapes of listing according to following mathematics deduction.On the contrary, the invention is intended to contain the real fluid flow path of the no groove polishing pad of equivalence in rotary course, and do not consider whether these flow paths are established by following desirable flow path Mathematical Modeling.

For the purpose of the aspect, fluid flow path 116 can be by the definition of many point, and these points have the polar coordinates that show radial position r and flow path angle θ, for example put 136 (r, θ).These points have defined the angular speed Ω of Utopian polishing medium at polishing pad 100 _pInfluence under, the patterns that outwards move along burnishing surface 104.In this embodiment, fluid flow path 116 is radial position r of polishing medium when increasing with respect to center of circle O, the changes delta θ of angular displacement.

In general, along with radial position r increases with respect to center of circle O, polishing medium quickens continuously.Fluid flow path 116 may with polishing medium from the outside angular speed v when mobile of center of circle O _rRelevant.Angular speed v _rCan be described as the variation that records with respect to time t, see shown in the formula 1 apart from the radial position r of center of circle O.

$v_r=\frac{\mathrm{dr}}{\mathrm{dt}}$ Formula { 1}

Be readily appreciated that, as the angular speed Ω of polishing pad 100 to fix _pRotation time, be applied to centripetal force on the polishing medium make described polishing medium when burnishing surface 104 outwards moves, obtain acceleration a (in order to simplify Mathematical Modeling, suppose once more described burnishing surface 104 for unnotched, smoothly dredge fluidic).Acceleration a sees formula 2.

$a=\frac{{\mathrm{dv}}_r}{\mathrm{dt}}=r{{\mathrm{\&Omega;}}_{\mathrm{<figure-callout\; id="2"\; label="p"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">p</figure-callout>}}}^2$ Formula { 2}

This acceleration increases along with the increase of the radial distance of distance center of circle O.The acceleration of this increase causes the angular speed v of increase _r, angular speed v _rCan be by (using initial angle velocity amplitude v _r=0) formula 2 is quadratured obtains, when described polishing medium being distributed on the burnishing surface 104 and do not produce the initial angle speed v _rThe time, can produce this situation.The results are shown in following formula 3.

v _r=r Ω _p ²T formula { 3}

Then, can as shown in Equation 4 formula 1 and formula 3 be combined, describe the variation of radial position r with respect to time t with this.Can carry out variables separation and integration to formula 4, obtain the result shown in the formula 5, wherein C is an integral constant.

$\frac{\mathrm{dr}}{\mathrm{dt}}=r{{\mathrm{\&Omega;}}_p}^{2}t$ Formula { 4}

$\ln \left(r\right)=\frac{1}{2}{\mathrm{\&Omega;}}^2{\mathrm{<figure-callout\; id="2"\; label="t"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">t</figure-callout>}}^2+C$ Formula { 5}

In addition, the changes delta θ of the angular displacement that the variation of radial position r can record with relative time t interrelates, shown in formula 6 and formula 7.

$t=\frac{\mathrm{\&Delta;\&theta;}}{{\mathrm{\&Omega;}}_p}$ Formula { 6}

$\ln \left(r\right)=\frac{1}{2}{\left(\mathrm{\&Delta;\&theta;}\right)}^2+C$ Formula { 7}

(work as r=r by the application boundary condition _oThe time Δ θ=0), can be sharp coming this formula is that formula 7 is determined the angular displacement Δ θ that change with radial position r, as shown in Equation 8.Under the situation about when radial position r increases with respect to center of circle O, quickening continuously, utilize the changes delta θ of the angular displacement of formula 8 descriptions can obtain the pattern that polishing medium outwards moves on the idealized burnishing surface 104 of rotation.

$\mathrm{\&theta;}=-\sqrt{2\ln \frac{r}{r_o}}$ Formula { 8}

The changes delta θ of angular displacement also can usually represent with radial position r, r=r (θ) for example, as shown in Equation 9.In one embodiment, the path that this formula is approximate when having determined that Utopian polishing medium moves freely on burnishing surface 104, promptly fluid flow path 116, and do not consider viscosity and capillary influence.

$r=r_o{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">e</figure-callout>}}^{\frac{1}{2}{\mathrm{\&theta;}}^2}$ Formula { 9}

In view of foregoing, a kind of method of the groove shapes 112 (Fig. 1) of polishing pad 100 each grooves 108 that determines is, makes the fluid flow path quadrature of determining with top formula 8 and formula 9 at least greatly of each groove.In this way, can make groove 108 form given shape, it applies reaction to various forms of motions as mentioned above, thereby hinders the motion of polishing medium.

In order to determine the formula with the groove shapes (for example groove shapes 112) of fluid flow path 116 quadratures, should know the slope s of fluid flow path.In general, see formula 10 with the slope of the fluid flow path 116 of polar coordinates function #=θ (r) expression.

$s=\frac{1}{r}\frac{\mathrm{dr}}{\mathrm{d\&theta;}}=\frac{1/r}{\mathrm{d\&theta;}/\mathrm{dr}}$ Formula { 10}

Can utilize the deduction (formula 10) of the fluid flow path 116 that formula 8 is reflected to determine the slope (formula 12) of flow path 116.

$\frac{\mathrm{d\&theta;}}{\mathrm{dr}}=\frac{-1}{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">r</figure-callout>}\sqrt{2\ln \frac{r}{r_o}}}$ Formula { 11}

$s=-\sqrt{2\ln \frac{r}{r_o}}$ Formula { 12}

In order to realize quadrature, the slope s of groove shapes 112 ^*Must make for points all on the fluid flow path 116 slope s and slope s ^*Long-pending be-1.Therefore, with the slope s of the groove shapes 112 of fluid flow path 116 quadratures ^*Determine by following formula 13:

$s^{*}={\left(\sqrt{2\ln \frac{r}{r_o}}\right)}^{-1}$ Formula { 13}

The slope s of the groove shapes 112 that formula 13 is determined ^*Can combine with formula 10, determine the deduction result (formula 14) of orthogonal curvilinear.Then, can be by formula 14 being carried out variables separation and integration obtains quadrature flow path θ ^*=θ ^*(r) (formula 15).

${\left(\frac{\mathrm{dr}}{\mathrm{d\&theta;}}\right)}^{*}=\frac{\mathrm{<figure-callout\; id="2"\; label="r"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">r</figure-callout>}}{\sqrt{2\ln \frac{r}{r_o}}}$ Formula { 14}

${\mathrm{\&theta;}}^{*}=\frac{1}{3}{\left(2\ln \frac{r}{r_o}\right)}^{3/2}$ Formula { 15}

Find the solution by the r to formula 15, the quadrature flow path also can be expressed as r ^*=r ^*(θ), as shown in Equation 16.

$r^{*}=r_o{\mathrm{<figure-callout\; id="1"\; label="e"\; filenames="S2008100054148E00011.png"\; state="\{\{state\}\}">e</figure-callout>}}^{\frac{1}{2}{\left(3\mathrm{\&theta;}\right)}^{2/3}}$ Formula { 16}

Referring to Fig. 3,,, make at least a portion length of corresponding recesses 108 and fluid flow path 116 quadratures that then groove can be as required repeatedly around polishing pad 100, as shown in Figure 1 in case groove shapes 112 (Fig. 3) is established simultaneously referring to Fig. 1.If each groove part extends to its outer periphery from the center of polishing pad 100, just can obtain best polishing medium and keep effect, but recognize in some embodiments, need make that groove is a quadrature less than the part of total length, promptly become 45-135 ° local angle with fluid flow path.But in general, need the quadrature component of each groove to extend through at least 50% of wafer track width, in Fig. 1, be shown as 140.For example, each groove 108 that shows among Fig. 1 is along its whole length and fluid flow path 116 quadratures.

For above-mentioned principle is described, Fig. 4-7 has shown other polishing pad 200,300, has only shown two kinds in the many other groove design that can use these principle preparations among the figure.At first referring to Fig. 4 and Fig. 5, polishing pad 200 comprises plurality of grooves 204 (Fig. 5), each groove 204 comprises interior section 204A, described interior section A under the situation of not considering fluid flow path 208, be shaped (Fig. 4), has the United States Patent (USP) the 6th that Muldowney obtained the authorization on August 31st, 2004,783, the advantage that is disclosed among No. 436 " having polishing pad of optimized groove and forming method thereof " (Polishing Pad with Optimized Grooves and Method of Forming Same), the document is incorporated by reference into herein.Each groove (Fig. 5) in described a plurality of groove 204 also can comprise exterior section 204B, and the shaping of this exterior section 204B makes itself and fluid flow path quadrature.In this embodiment, each interior section 204A of described a plurality of groove 204 extends to radius R near the point polishing pad 200 center of circle O ₁The point (Fig. 4) at place is about 1/3 of polishing pad radius herein.The quadrature exterior section 204B of described each groove 204 is from corresponding radius R ₁The each point at place extends to radius R ₂, radius R ₂Whole radiuses for for example polishing pad 200.As can be seen, about 4/5 of wafer track 212 width W comprise the quadrature exterior section 204B of described groove in Fig. 5.

Next referring to Fig. 6 and Fig. 7, polishing pad 300 comprises a plurality of being designed to and the opposite groove 304 of groove 204 among Fig. 5.That is to say, not to make the quadrature component of groove be positioned at the radial outside of non-orthogonal part substantially, but make the shape and fluid flow path 308 quadratures (Fig. 6) of interior section 304A (Fig. 7) of each groove 304 of polishing pad 300, the shape of exterior section 304B does not consider to make itself and fluid flow path quadrature, it has United States Patent (USP) mentioned above the 6th, the advantage that is disclosed for 783, No. 436.In this embodiment, each quadrature interior section 304A is near the radius R center of circle O of polishing pad 300 ₁' the point located extends to radius R ₂' the point located, in the case, R ₂' be about 2/3 of the total radius of polishing pad.Corresponding each not deliberately the exterior section 304B of quadrature from radius R ₂' the point of locating extends to the outer periphery of polishing pad 300.Can find out at an easy rate from Fig. 7, wafer track 312 width W ' the about 2/3 quadrature interior section 304A that comprises groove 304.

Although it will be appreciated by those skilled in the art that Fig. 5 further groove 204 not deliberately the groove 304 of the interior section 204A of quadrature and Fig. 7 not deliberately the exterior section 304B of quadrature all be shown as spiral, and nonessential like this.For example, in other embodiment, described spiral groove can replace with the groove of other shape and orientation, for example straight and spiral, slight curving and radially, tortuous and radially, tortuous and hoop, corrugated and radially and corrugated and hoop.The not part of intentional quadrature of described groove can randomly be the stack of other simpler groove pattern also, for example stack of the stack of Descartes's grill-shaped or grid and circle or spirality pattern.In addition, other embodiment can have other groove configuration.For example, some embodiments can be the heterozygotes of the polishing pad 200,300 of Fig. 5 and Fig. 7.That is to say that other embodiment may comprise the groove with following characteristics: the shape of these some parts of groove is with respect to the fluid flow path quadrature, and its inside and outside part is not deliberately and the fluid flow path quadrature.

Fig. 8 shown and is suitable for using polishing pad 404 to come the polishing machine 400 of polished product (for example wafer 408), and described polishing pad 404 can be a kind of in the polishing pad 100,200,300 among Fig. 1-7, or other polishing pad constructed in accordance.Polishing machine 400 can comprise workbench 412, and polishing pad 404 is mounted thereto.Can described workbench 412 be rotated around rotation A1 by the table driver (not shown).Polishing machine 400 also can comprise chip support 420, and this support 420 can be around rotation A2 rotation, and this rotation A2 is parallel with the rotation A1 of workbench 412, and is spaced from, this support 420 supporting wafers 408 in polishing process.Chip support 420 can have the universal connecting components (not shown), and this universal connecting components allows wafer 408 to be the form that the utmost point is not parallel to the burnishing surface 424 of polishing pad 404 slightly, and wherein rotating shaft A1, A2 can tilt mutually extremely slightly.Wafer 408 comprises polished surface 428, and it is flattened in polishing process towards burnishing surface 424.Chip support 420 can be supported by stent support assembly (not shown), described assembly is suitable for making wafer 408 rotations, and downward directed force F is provided, so that polished surface 424 is pressed against on the polishing pad 404, make in polishing process, to have required pressure between the polished surface and polishing pad.Polishing machine 400 also can comprise polishing medium inlet 432, is used for carrying polishing medium 436 to burnishing surface 424.

Those skilled in the art can understand, polishing machine 400 can comprise other parts (not shown), for example system controller, polishing medium storage and distribution system, heating system, rinse-system and the various controllers that are used for controlling the polishing process various aspects, for example: (1) is used for controlling the speed control and the selector of wafer 408 and 404 1 of polishing pads or both rotating speeds; (2) be used for changing to the speed of polishing pad conveying polishing medium 436 and the controller and the selector of position; (3) be used for controlling the controller and the selector of the size that is applied to the directed force F between wafer and the polishing pad; And (4) be used for controlling controller, actuator and the selector of the rotation A2 of wafer with respect to the position of polishing pad rotation A1, or the like.Those skilled in the art are to be understood that how to construct and use these parts, therefore need not to describe in detail, and those skilled in the art just can understand and implement the present invention.

In polishing process, polishing pad 404 and wafer 408 are distributed in polishing medium 436 on the polishing pad of rotation from polishing medium import 432 around its rotation A1, A2 rotation separately.Polishing medium 436 launches on burnishing surface 424, comprises in the gap that spreads between wafer 408 and the polishing pad 404.Polishing pad 404 and wafer 408 common (but not necessarily) rotate under 0.1-850 rev/min selected speed.The size common (but not necessarily) of selected directed force F causes required 0.1-15 pound/inch between wafer 408 and polishing pad 404 ²The pressure of (6.9-103 kPa).

Claims (10)

1. one kind is used for the polishing pad that is used in combination with polishing medium, and it has rotating polishing pad in use and the perfect fluid flow path that obtains, and described polishing pad comprises:

(a) design is used in the presence of polishing medium at least a polishing layer that polishes in magnetic base material, optical element and the semiconductor substrate, and described polishing layer comprises circular burnishing surface, and this burnishing surface has the annular polishing track in polishing process;

(b) be formed at least one interior groove of described polishing layer, it has the quadrature component that is positioned at described polishing locus, and described quadrature component has certain-length, is shaped along whole length, is configured as along quadrature component and perfect fluid flow path quadrature.

2. polishing pad as claimed in claim 1 is characterized in that described polishing locus has certain width, and described quadrature component is across at least 50% of this width.

3. polishing pad as claimed in claim 2 is characterized in that described quadrature component is across at least 75% of described polishing locus width.

4. polishing pad as claimed in claim 1 is characterized in that it comprises a plurality of grooves, and these groove part ground repeat to determine around described burnishing surface by making described quadrature component.

5. polishing pad as claimed in claim 4 is characterized in that, described a plurality of groove parts ground repeats to determine around described burnishing surface with fixing angular pitch by making described quadrature component.

6. polishing pad as claimed in claim 1 is characterized in that, the shape of described quadrature component is determined by following formula:

$r^{*}=r_o{e}^{\frac{1}{2}{\left(3\mathrm{\&theta;}\right)}^{2/3}}$

R in the formula _oBe the initial radial position apart from the polishing pad center of circle, θ is the flow path angle.

7. polishing pad, it comprises:

(a) design is used in the presence of polishing medium at least a polishing layer that polishes in magnetic base material, optical element and the semiconductor substrate;

(b) be formed at least one groove in the described polishing layer, it has the quadrature component that is positioned at polishing locus, and described quadrature component has certain-length, is shaped according to following formula

$r^{*}=r_o{e}^{\frac{1}{2}{\left(3\mathrm{\&theta;}\right)}^{2/3}}$

R in the formula _oBe and the center of circle initial axial location apart of polishing pad, θ is the flow path angle.

8. polishing pad as claimed in claim 7 is characterized in that, in polishing process, described burnishing surface comprises the polishing locus with certain width, and described quadrature component is across at least 50% of described width.

9. polishing pad as claimed in claim 7 is characterized in that described polishing pad comprises a plurality of grooves, and these groove part ground repeat to determine around described burnishing surface with fixing angular pitch by making described quadrature component.

10. preparation method who is used for the rotating polishing pad that uses with polishing medium as claimed in claim 1, this method comprises:

Determine the flow path of polishing medium;

Groove shapes and the groove orientation determining in rotating polishing pad, to form as the groove of the function of polishing medium flow path;

In described rotating polishing pad, form the groove that has described groove shapes and groove orientation in a large number.

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